Subset x `D` {
    x.color = computeColorRGBA(0.1, 1.0, 0.2, 0.4) -- green
    constraint contains(y, x)
    constraint smallerThan(x, y)
    constraint outsideOf(y.label, x)
}

Set x {
    shape = Circle { }
    constraint contains(x, x.label)
}
